Cathodic protection for water softeners and filters



G. H. KLUMB July 17, 1951 CATHODIC PROTECTION FOR WATER SOFTENERS AND FILTERS Filed Sept. 14, 1948 m m m we Patented July 17, 1951 CATHODIC PROTECTION FOR WATER SOFTENERS AND FILTERS George H. Klumb, Northbrook, Ill., assignor to Culligan Zeolite Company, Northbrook, Ill., a

corporation of Delaware Application September 14, 1948, Serial No. 49,163

Claims. (01. 204-497) The present invention relates to cathodic pro tection for water softeners and filters and especially to a novel means and manner of maintaining liquid fiow through a water softener or filter in which a sacrificial anode is employed.

Cathodic protection has been employed for the protection against corrosion of underground pipe lines and water storage tanks by the use of an expendable or sacrificial anode.

In such water tanks the expendable anode is connected electrically to the tank or through a resistor for regulating the current flow. Such corrosion in an aqueous media is electro-chemical .in nature in which galvanic cells are established through either the use of dissimilar metals in the construction or fabrication of the tanks, or due to the many anodes and cathodes of the metal used in their fabrication. The water stored in the tanks acts as an electrolyte whereby positive electric current flows from the anode to the cathode and results in solution of the metal constituting the anodic area and subsequent tank failure from the resulting corrosion.

By the use of a sacrificial anode suchas a magnesium rod, or in some cases one formed of zinc or aluminum, such corrosion is substantially or entirely prevented by neutralizing the local action currents and currents resulting from the use of dissimilar metals. By providing such magnesium anode in the system, there is produced the necessary current without an external source of electric energy, and such sacrificial anode also protects the tank walls from corrosion by the formation of a calcareous coating thereon and upon the other cathodic areas within, the tank.

In the protection of water heaters or other tanks where the inlet and outlet openings are relatively large, the formation .of a calcareous coating constitutes no problem. However, in tanks such as employed in water softeners and filters containing a bed of granular material through which the water must pass in its treatment, some type or form of distributor or manifold must be provided to disperse the water at theinlet and collect at the outlet so that the water after passing through the bed may be with drawn but without carrying along the granular" material which is retained in the tank and pre-' vented from leaving. Such distributors or manifolds are generally constructed of brass or of other metal that is cathodic to the tank and thus plating or collection of the calcareous coating upon the distributor occurs when a sacrificial anode is used. This coating results in impeding or restricting and subsequent blocking of the flow of water through the distributor.

It is, therefore, an object of the present invention to provide a novel means and manner of maintaining flow through water softeners and filters in which sacrificial anodes are employed. More particularly, the invention comprehends a novel means and manner of cathodic protection in which the outlet and inlet manifolds or distributors are electrically insulated whereby such members are prevented from becoming cathodic with respect to the anode and tank.

v The present invention further comprehends a novel means and method of preventing restriction or stoppage of water flow through the distributors or manifolds of a water softening or filter tank by preventing the formation of a calcareous coating when a sacrificial anode is em ployed in the tank of such water softener or filter.

Further objects are to provide a construction of maximum simplicity, efficiency, economy and ease of assembly and operation, and such further objects, advantages and capabilities as will later more fully appear and are inherently possessed thereby.

The invention further resides in the construction, combination and arrangement of parts illustrated in the accompanying drawing, and while there is shown therein a preferred embodiment, it is .to be understood that the same is susceptible of modification and change, and comprehends other details, arrangements of parts, features and constructions without departing from the spirit of the invention.

In the drawing:

Figure 1 is a view in vertical cross section through the tank of a water softener unit.

' Fig. 2 is a fragmentary enlarged view, part in vertical cross section and part in side elevation,

of the novel distributor or manifold.

Fig. 3 is a view, part in vertical cross section and part in side elevation, of a water softener tank provided with an alternate form or embodimerit of protective means.

Fig. 4 is a fragmentary enlarged view in vertical cross section showing another embodiment or manner of insulating the distributor tubes or pipes from the metal tank.

. Referring more particularly to the construction disclosed in Figs. 1 and 2 of the drawing, the em-.

bodiment therein selected to illustrate the present invention comprises a water softener unit I including a metal tank 2 which may be rendered corrosion-resistant by galvanizing or .the like,

In the head treated water or other liquid, and extending to approximately the bottom of the tank where it is provided with a distributor or manifold'fl ad fluent its lower end having a plurality of :relatively closely spaced and laterally disposed slots .or ports it] through which the treated water passes, {.The fitting i carries a relatively short and depending pipe or tube II also provided with a distributor or manifold 12 adjacent its lower end. This pipe or tube normally provides an inlet for the .entering untreated water which passes downwardly through this manifold and outwardly through .a plurality of closed arranged and laterall disposed slots is similar to those in the distributor or'manifold 9. Each distributor or manifold 9 and i2 is closed at its lower end l3 whereby the liquid must pass through the slots when leaving the inlet pipe or tube 8 and when entering the outlet pipe or tube II.

A sacrificial anode is projecting upwardlyinto the tank 2 is mounted at its lower end in a fitting l detachably mounted in the bottom 4 of the tank 2, and with its upper end projecting adjacent to but spaced from the underside of the head 3. This anode preferably comprises a magnesium rod for substantially preventing corrosion by neutralizing the local action currents andthose resulting from the use of dissimilar metals. It is not connected to anyexternal circuit or source of electrical energy, but produces the necessary current whereby the interior walls of the tank are protected against corrosioniby superimposing, by means of the sacrificial anode, a current in the opposite direction of that between dissimilar metals and the anodic and cathodic areas in one metal, of such intensity as to cancel the normal current flow causing such corrosion and to further protect against corrosion by the formation of a calcareous coating on these walls and on other cathodic areas within the tank. As the distributors or manifolds are normally cathodic to the tank, this calcareous coating produced by the rod would collect on the distributors or manifolds and in the slots thereof unless these distributors or manifolds are protected against such clogging. These slots being normally, of a size to permit the uninterrupted passage of the liquid but to prevent passage therethrough of the granular material forming the bed A. through which passes the. liquid to be treated, are soon clb gedby such calcareous coating resultingin stoppage of the liquid flow due to the blocking of the slots. r I

I To prevent the distributors or-manifolds 9 and i2 from becoming cathodic and thereby'avoid the collection thereon andv in their solts or ports of the calcareous coating, they are insulated from the remainder of the tubes or pipes 8 and II, respectively, by an insulating sleeve I B which couples or joins these parts but insulates the distributors or manifolds from any cathodic parts or areas. This sleeve is of a non-metallic insulating' material such as an acetate, natural or compounded synthetic rubber, or other plastic composition having the desired insulating qualities, and may be crimped at 24 or otherwise affixed to "tank and other cathodic areas.

the adjoining ends of the pipe or tube and its manifold.

In Fig. 3 is shown another embodiment of the invention in which the outlet pipe I! and its distributor or manifold l8, and the inlet pipe l9 and its distri u r Or nifoldzfl are, formed. integral and ofa non-metallic and preferably-plasticfcomposition having the desired insulating qualities for insulating the entire tube assemblies from the .ig. 114 shows .:.another means and manner of insulating, the outlet and inlet pipes or tubes and their distributors or. manifolds from theftank andother cathodic areas. In this form of the invention, thegfitting or coupling 21 for detachably mounting the outlet tube or pipe 22 and its manifold or distributor in the head 3 of the tank 2,

is, insulated from the metal pipe or tube 22 by a non-metallic, insulating sleeve or bushing 23 which may be of any suitable plastic material. The inlet pipe (not shown) may be similarly in sulated so as to prevent the slots'or ports its distributor'or manifold from becoming clogged, and instead of providing the insulating sleeve between the'distributor' tube 22 and the fitting, it maybe provided between the fitting and the head 3 of the tank. I v

' Although I have referred to the longer pipe'or tube as the outlet and the shorter as the inlet,-it will beappreciate'd that'theflow may be reversed and instead of theliquid tobe treated passing through the bed of granular material in a down- .fiow direction, it may pass inan 'upflow directiofil Also although I have referred more particularly to a'water softener tank, the inventioncompra; hends the use in a tank suitable for either-a water softening or filtering operation where the liquid being treated is passedthrough a bed or mass'of granular particles.

. In the disclosed embodiment, the bed A organ;

u-larmaterial in the tank is shown-as consisting of an upper and relatively deep layer or mass. fof zeolite or other water treating material .or particles-an intermediate layer of relatively fine gravel and a bottomlayer-of relatively coarse ravel. However, it is to be understood that the invention is not limited thereto.

Having thus disclosed the invention, I claim:

1. In a metal tankof the class described, a bed containing cation exchange material, an inlet and outlet for the water tobe treated, a metal manifold on said inlet and a metal manifold on said outlet both within the tank and eachihavingia plurality of closelyspaced openings of suchfdimensions as topermit an uninterrupted .flow of the water butsmall enough to prevent normal passage therethrough of the exchange materialofv the bed.-a sacrificial galvanic anode in and electrically connected to said-tank and projecting into the bed of material for protecting thetank walls againstcorrosion byreversal of current flow and by formation of a calcareous coating,"said tank, inlet and outlet being of metal and providing cathodic areas, and insulating means between each manifold and these cathodic areas for'electrically insulating the manifold therefrom to'prevent the coating from the; anode fromcollecting on and in the openings of the manifoldand thereby assuring uninterrupted flow through these openings. I r

2.- ,Ina metal tank of theclass described,-a bed of material containing a cation exchanger for treatingthe water passing therethrough, a metal outlet fitting, a metaloutlet tube connected to and depending from the outlet fitting and'projecting into the interior of the tank and provided with a manifold having openings therein of a size less than the normal size of the adjacent material, said tank, outlet fitting and outlet tube providing cathodic areas, a sacrificial galvanic anode removably mounted in and electrically connected to the tank and extending substantially through the tank and into the bed of material, and a sleeve of insulating material connecting the outlet tube to the manifold but electrically insulating said manifold from the cathodic areas.

3. In a metal tank of the class described hav ing a deep stratified bed of loosely packed solid particles including cation exchange material and a sacrificial galvanic anode mounted in and electrically connected to the tank for protecting the tank walls against corrosion, a metal outlet fitting in the tank, a medal outlet manifold connected to the outlet fitting for the water to be treated and projecting into the tank and the bed of solid particles and exchange material where it is provided with a plurality of small openings for the uninterrupted passage therethrough of the Water but preventing passage of the exchange material, said tank and outlet fitting providing cathodic areas, and insulating means between the fitting and the manifold for insulating the latter from the cathodic areas of the tank and the metal fitting.

4. In a metal tank of the class described having a deep stratified bed of loosely packed solid particles including cation exchange material and a sacrificial galvanic anode electrically connected to and projecting into the tank and the bed therein, a metal outlet fitting in the tank and providing cathodic areas with the tank, a metal outlet tube having a manifold depending into the tank and into the bed, said manifold being closed at its lower end and adjacent thereto provided with closely spaced openings for the uninterrupted passage of the treated water but preventing the normal passage therethrough of the material of the bed, and a sleeve of insulation material between the outlet tube and its fitting.

5. In a metal tank of the class described containing a bed of solid material including a cation exchanger for treating Water and a sacrificial galvanic anode electrically connected to and projecting into the tank and the bed of material, a metal fitting in the tank for the passage of water, a metal tube connected to the fitting, the tank, fitting and tube providing cathodic areas, a metal manifold having laterally opening ports for the uninterrupted passage of water therethrough but preventing the normal passage therethrough of the solid material, and a sleeve of insulating material between and connecting the manifold to the tube.

GEORGE E. KLUMB.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,271,341 Johnson et a1 M Jan. 2'7, 1942 2,347,201 Lindsay Apr. 25, 1944 2,459,123 Bates et a1 Jan. 11, 1949 FOREIGN PATENTS Number Country Date 45,483 France May 27, 1935 Addition to No. 780,479

OTHER REFERENCES Corrosion, vol. 2, Oct. 1946, pages 175 thru 187.

Industrial & Engineering Chemistry, Sept. 1948, pages105a, 106a Certificate of Correction Patent No. 2,560,960 July 17, 1951 GEORGE H. KLUMB It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows:

Column 3, line 1, for take read tank; line 64', for solts read slots; column 5, line 18, for medal read metal;

and that the said Letters Patent should be read as corrected above, so that the same may conform to the record of the case in the Patent Ofiice. Signed and sealed this 25th day of September, A. D. 1951.

[SEAL] THOMAS F. MURPHY,

Assistant Oommz'ssz'oner of Patents. 

1. IN A METAL TANK OF THE CLASS DESCRIBED, A BED CONTAINING CATION EXCHANGE MATERIAL, AN INLET AND OUTLET FOR THE WATER TO BE TREATED, A METAL MANIFOLD ON SAID INLET AND A METAL MANIFOLD ON SAID OUTLET BOTH WITHIN THE TANK AND EACH HAVING A PLURALITY OF CLOSELY SPACED OPENINGS OF SUCH DIMENSIONS AS TO PERMIT AN UNINTERRUPTED FLOW OF THE WATER BUT SMALL ENOUGH TO PREVENT NORMAL PASSAGE THERETHROUGH OF THE EXCHANGE MATERIAL OF THE BED, A SACRIFICAL GALVANIC ANODE IN AND ELECTRICALLY CONNECTED TO SAID TANK AND PROJECTING INTO THE BED OF MATERIAL FOR PROTECTING THE TANK WALLS AGAINST CORROSION BY REVERSAL OF CURRENT FLOW AND BY FORMATION OF A CALCAREOUS COATING, SAID TANK, INLET AND OUTLET BEING OF METAL AND PROVIDING CATHODIC AREAS, AND INSULTING MEANS BETWEEN EACH MANIFOLD AND THESE CATHODIC AREAS FOR ELECTRICCALLY INSULATING THE MANIFOLD THEREFROM TO PREVENT THE COATING FROM THE ANODE FROM COLLECTING ON AND IN THE OPENINGS OF THE MANIFOLD AND THEREBY ASSURING UNINTERRUPTED FLOW THROUGH THESE OPENINGS. 